1. Field of the Art
This invention relates to a vibration machining method in which cutting of a workpiece is accomplished by imparting vibration to the cutting tool of a cutting device. The invention relates also to a cutting device for the method. More particularly, the invention relates to a method and a device wherein the cutting edge is inclined relative to the cutting direction, and the cutting part of the cutting tool is vibrated along the cutting edge.
2. Prior Art
In general, the vibration cutting method is which cutting is carried out by vibrating a cutting tool in parallel to the cutting speed direction is known (for example, Japanese Patent Publication No. 36-18897). According to this vibration cutting method for the prior art, cutting is accomplished by holding the cutting edge of the cutting tool substantially perpendicularly to the cutting speed direction and vibrating the cutting tool in the direction perpendicular to the cutting edge, that is, in parallel to the cutting speed direction.
By the above described vibration cutting method, limiting the cutting speed is unavoidably necessary in order to enable the cutting fluid to infiltrate and flow between the chip and the cutting tool face during cutting. That is, the cutting speed v must satisfy the following conditional relationship. EQU v&lt;2.pi.a.function.,
where
a is the vibrational amplitude, and
.function. is the vibrational frequency.
Furthermore, high power has been necessary for vibrating the cutting tool in the direction perpendicular to its cutting edge. Accordingly, a cutting tool having a cutting edge of narrow width and a sharp point has been generally used.
In the above described known method of vibration cutting, the workpieace is cut by vibrating the cutting tool of sharp point in a manner to satisfy the conditional relationship set forth hereinbefore. For this reason, it has been necessary to use a low cutting speed and, moreover, a low rate of feed. Consequently there has been the problem of low machining efficiency.
Furthermore, high power has been required to impart vibration. Consequently the power efficiency for machining has been low. Moreover, the serviceable life of the cutting tool is shortened.